In a wideband code division multiple access (WCDMA) cellular network, cells served by a base station have respective coverage areas, and provide downlink services to UEs within the respective coverage areas. To achieve highest frequency spectrum efficiency, the WCDMA cellular network generally uses a single-frequency network manner. That is, all neighboring cells use a same carrier. Therefore, coverage areas of cells whose frequency bands are the same may overlap. For UE within an overlapped area, downlink signals of two or even more cells are likely to be received at the same time. When intra-frequency signals from the cells are relatively strong, the UE suffers from severe interference, affecting communication quality.
As shown in FIG. 1, user equipment 1 is within an overlapped coverage area of two cells of a same base station (i.e., abase station 1), and user equipment 2 is within an overlapped coverage area of two cells of different base stations (i.e., the base station 1 and a base station 2, where a radio access standard (i.e., Radio Access Technology) of the base station 1 may be any one of universal mobile telecommunications system (UMTS), long term evolution (LTE), global system for mobile communication (GSM), or code division multiple access (CDMA), and a radio access standard of the base station 2 may be any one of UMTS, LTE, GSM, or CDMA). Assuming that a serving cell of the user equipment 1 is the cell 1, a signal transmitted by the cell 2 is an interfering signal for the user equipment 1. Assuming that a serving cell of the user equipment 2 is the cell 2, regardless of whether a radio access standard of the cell 2 is the same as a radio access standard of a cell 3, a signal transmitted by the cell 3 is also an interfering signal for the user equipment 2. For the user equipment 1, the user equipment 1 needs to cancel interference of the interfering signal (i.e., the signal of the cell 2) to improve downlink service quality of the user equipment 1. However, in the prior art, the user equipment 1 does not know a transmitting manner (including a modulation mode, a used single-antenna or multiple-antenna manner or precoding control indication (PCI) manner, and the like) supported by the cell 2. Therefore, the user equipment 1 needs to detect, among all possibly supported transmitting manners, a transmitting manner being used by the cell 2. Relatively many resources are needed to complete detection work, and moreover, detection accuracy is also reduced. For example, a modulation mode used when a cell transmits a signal includes quadrature phase shift keying (QPSK), quadrature amplitude modulation (e.g., 16QAM, 64QAM, 256QAM). The user equipment 1 needs to detect, among all the foregoing possible modulation modes, a modulation mode being used by the cell 2. When the user equipment 1 considers, after detection, that the cell 2 is using 64QAM, if the cell 2 uses only the modulation modes QPSK and 16QAM and does not use 64QAM and 256QAM, the detection by the user equipment 1 is incorrect, and interference of the interfering signal from the cell 2 cannot be canceled.